The response of sea ice and brine water algae and bacteria to changes in salinity, temperature, light and UVB in Terra Nova Bay

Samples of the bottom ice algae and brine algae (within 30cm of the top of the ice) were subjected to temperature, salinity, light and UVB experiments and analysed with PAM rapid light curves to determine the response of the algae to changes they will encounter during the processes of ice formation at the start of winter and ice melting in summer. Brine algae are likely to be adapted to high light and high UVB conditions near the surface of the ice and may have produced higher levels of protective pigments, MAA's, therefore the content of MAA's was analysed.

Imaging PAM fluorometry was also used to gain a 3D image of photosynthetic stressors during the process of ice freeze and thaw on both algae and bacterial cells. The difference in thylakoid structure with increase in temperature was also analysed. Bacterial cells were collected at the end of exposure and a CTC assay was performed on them to determine the effect of UVB radiation.